From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Hering <olaf@aepfle.de>
Subject: Re: [PATCH 2 of 4 RFC] xen,
 pod: Check zero-check pages returned by the balloon driver
Date: Thu, 14 Jun 2012 15:19:23 +0200
Message-ID: <20120614131923.GA9349@aepfle.de>
References: <patchbomb.1339156490@elijah>
	<8264589787b484b7f903.1339156492@elijah>
	<20120614102808.GI82539@ocelot.phlegethon.org>
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To: Tim Deegan <tim@xen.org>
Cc: George Dunlap <george.dunlap@eu.citrix.com>, xen-devel@lists.xensource.com, Andres Lagar-Cavilla <andres@lagarcavilla.org>
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On Thu, Jun 14, Tim Deegan wrote:

> At 12:54 +0100 on 08 Jun (1339160092), George Dunlap wrote:
> > +        else if( p2m_is_ram(t) )
> > +        {
> > +            if ( steal_for_cache )
> > +            {
> > +                struct page_info *page;
> > +                
> > +                ASSERT(mfn_valid(mfn));
> 
> I think this assertion is broken by the paging code, which adds
> paged-out pages to the RAM types.  One fix is to undo that change and
> have p2m_is_ram() only be true for present pages, but I think for 4.2 it
> would be less disruptive to test here for the paged-out and paging
> types.

I assume the posted hunk is in PoD code, for 4.2 it should be fine
because paging cant be enabled if PoD is already enabled.

Olaf